Malononitrile → 2-Amino-4-benzyl-3-cyano-5-hydroxynaphtho[1,2-b]furan

A mixture of potassium hydride (7.56 g, 63 mmol, 35% oil dispersion) and hexane (250ml) was stirred at room temperature under nitrogen. Solvent was decanted off and substituted with dry tetrahydrofuran (250ml). Malononitrile (4.16 g, 63 mmol), dissolved in tetrahydrofuran (50 ml), was then added to the slurry dropwise. A mixture of 2-benzyl-1,4-naphthoquinone (15.62 g, 63 mmol) and tetrahydrofuran (50 ml) was then added dropwise. The reaction mixture was set at reflux for 2h, allowed to cool to room temperature and quenched with methanol (50 ml). The mixture was poured into water (100 ml) and extracted into ethyl acetate (3 x 250 ml). The organic layer was dried (magnesium sulfate) and evaporated to an oil. Chromatography (silica gel: hexane/ethyl acetate (2 : 1) as eluant) of the oily residue afforded 7.48 g (23 mmol, 38%) of product as green crystals, m.p. 224°-225 ° C.; 1H NMR (d6DMSO): 4.5(s,2H), 7.1-7.6 (m, 7H), 7.9(d, 1H), 9.25(s, 1H); IR (nujol): 3460, 3310, 3240, 3190, 2220; High resolution mass spectrum: calculated 314.1055, measured 314.1061.

1. customSolvent was decanted off
2. additionwas then added to the slurry dropwise
3. additionwas then added dropwise
4. temperatureto cool to room temperature
5. customquenched with methanol (50 ml)
6. additionThe mixture was poured into water (100 ml)
7. extractionextracted into ethyl acetate (3 x 250 ml)
8. dry with materialThe organic layer was dried (magnesium sulfate)
9. customevaporated to an oil

ORD record

ord-7c77004a91ef499285caec4cc6c25cf0

Source dataset

uspto-grants-1993_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05244917